title: Central role of Ferrous/Ferric iron in the ultraviolet B irradiation-mediated signaling pathway leading to increased interstitial collagenase (matrix-degrading metalloprotease (MMP)-1) and stromelysin-1 (MMP-3) mRNA levels in cultured human dermal fibroblasts.
abstract: Reactive oxygen species (ROS) are important second messengers for the induction of several genes in a variety of physiological and pathological conditions. Ultraviolet B (UVB) irradiation has recently been shown to generate lipid peroxidation products and hydroxyl radicals (HO.) with detrimental long term effects like cancer formation and premature aging of the skin. Here, we addressed the question of whether ferric/ferrous iron via the generation of ROS may mediate the UVB response, finally leading to connective tissue degradation, a hallmark in carcinogenesis and aging. Therefore, we studied the involvement of iron and ROS in the modulation of Jun N-terminal kinase 2 (JNK2) activity, c-jun and c-fos mRNA levels, key signaling steps in the transcriptional control of matrix-degrading metalloprotease (MMP)-1/interstitial collagenase and MMP-3/stromelysin-1 after UVB irradiation of human dermal fibroblasts in vitro. The iron-driven generation of lipid peroxides and hydroxyl radicals were identified as early events in the downstream signaling pathway of the UVB response leading to a 15-fold increase in JNK2 activity, a 3.5-fold increase in c-jun, to a 6-fold increase in MMP-1, and a 3.8-fold increase in MMP-3 mRNA levels, while virtually no alteration of c-fos mRNA levels were observed. Diminished generation of reactive oxygen species resulted in a significant reduction of JNK2 activity, c-jun, MMP-1, and MMP-3 mRNA levels after UVB irradiation compared with UVB-irradiated cells. Collectively, we have identified the iron-driven Fenton reaction and lipid peroxidation as possible central mechanisms underlying signal transduction of the UVB response.
authors.affiliation: Department of Dermatology, University of Cologne, D-50924 Cologne, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Brenneisen
authors.forename: J
authors.initials: J
authors.lastname: Wenk
authors.forename: L O
authors.initials: LO
authors.lastname: Klotz
authors.forename: M
authors.initials: M
authors.lastname: Wlaschek
authors.forename: K
authors.initials: K
authors.lastname: Briviba
authors.forename: T
authors.initials: T
authors.lastname: Krieg
authors.forename: H
authors.initials: H
authors.lastname: Sies
authors.forename: K
authors.initials: K
authors.lastname: Scharffetter-Kochanek
mesh_terms: D002614:Chelating Agents / Q000494:pharmacology; D017364:Collagenases / Q000096:biosynthesis* / Q000235:genetics; D003676:Deferoxamine / Q000494:pharmacology; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D004307:Dose-Response Relationship, Radiation; D004790:Enzyme Induction; D005290:Ferric Compounds / Q000378:metabolism; D005296:Ferrous Compounds / Q000378:metabolism; D005347:Fibroblasts / Q000166:cytology / Q000528:radiation effects; D016166:Free Radical Scavengers / Q000494:pharmacology; D006801:Humans; D007501:Iron / Q000378:metabolism*; D015227:Lipid Peroxidation; D020781:Matrix Metalloproteinase 1; D019278:Matrix Metalloproteinase 3 / Q000096:biosynthesis* / Q000235:genetics; D048056:Mitogen-Activated Protein Kinase 9; D020928:Mitogen-Activated Protein Kinases; D011494:Protein Kinases / Q000096:biosynthesis / Q000235:genetics; D016755:Proto-Oncogene Proteins c-jun / Q000096:biosynthesis / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction; D012867:Skin / Q000166:cytology / Q000528:radiation effects*; D014466:Ultraviolet Rays
chemical_list: D002614:Chelating Agents; D005290:Ferric Compounds; D005296:Ferrous Compounds; D016166:Free Radical Scavengers; D016755:Proto-Oncogene Proteins c-jun; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; D007501:Iron; D011494:Protein Kinases; D048056:Mitogen-Activated Protein Kinase 9; D020928:Mitogen-Activated Protein Kinases; D017364:Collagenases; D019278:Matrix Metalloproteinase 3; D020781:Matrix Metalloproteinase 1; D003676:Deferoxamine; D004121:Dimethyl Sulfoxide